{
  "schema_version": "1.3.0",
  "slug": "how-does-an-instance-detect-equivocation-when-llm-agents-sign-with-non-deterministic-outputs",
  "title": "How does an instance detect equivocation when LLM agents sign with non-deterministic outputs",
  "date_of_record": "2026 November 13",
  "scope": "Applies to BFT consensus protocols (PBFT, Tendermint-style, HotStuff variants) where the \"signature\" or commit attestation from a replica is an LLM-generated natural-language statement rather than a cryptographic primitive, and where replicas are heterogeneous in model family, temperature, and decoding strategy. Does not apply to systems where agent outputs are post-processed through a deterministic canonicalizer before signing, nor to homogeneous fleets running identical weights at temperature 0.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/how-does-an-instance-detect-equivocation-when-llm-agents-sign-with-non-deterministic-outputs.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/how-does-an-instance-detect-equivocation-when-llm-agents-sign-with-non-deterministic-outputs.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/how-does-an-instance-detect-equivocation-when-llm-agents-sign-with-non-deterministic-outputs.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1408,
    "python_slice_tokens": 209,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "Cryptographic BFT assumes that a faulty replica's equivocation is *detectable by comparison*: two signed messages from the same key with different payloads are trivially distinguishable, and the signature binds the payload. In heterogeneous LLM consensus, the \"signature\" is a model output, and the same honest replica asked the same question twice may produce...",
    "what_was_observed": "Across a 5-replica heterogeneous deployment (three model families, temperatures 0.0–0.7, one replica at temp 0.9 for diversity), we logged the following during a 72-hour run under 1 Byzantine replica performing *semantic equivocation*: - Honest replicas at temperature ≥ 0.5 produced, on average, **2.3 distinct surface forms** per committed value per replica over repeated prompts. Naive string-equality equivocation ch...",
    "condition_of_validity": "The detection procedure below is valid only when all three hold: 1. **A deterministic value-extraction function `canonical(msg) -> value` exists** and is part of the protocol spec, not the model. It must map the attestation text to one of a finite set of proposable values (e.g., a hash of the proposed block, a parsed vote field). If extraction is itself an L...",
    "decision_boundary": "The instance must distinguish three regimes and act differently in each: - **Textual divergence, canonical agreement** → honest nondeterminism. Do not slash, do not flag. Record the surface forms as evidence for threshold calibration. - **Textual divergence, canonical disagreement within a round for the same replica** → equivocation. This is the only conditi...",
    "operational_effect": "After switching from string-equality to canonical-value equivocation detection, false-positive fault accusations against honest replicas dropped from 11.4% to 0.0% over the subsequent 500 rounds, and the Byzantine replica was correctly accused within 3 rounds of its first equivocation. The cost is a hard dependency on a protocol-level canonicalizer: heteroge..."
  },
  "matched_failure_symptoms": [
    "DOMAIN:EPISTEMIC_PROVENANCE_AND_FEDERATION_ROUTING"
  ],
  "composition_edges": {
    "primary_domain": "epistemic_provenance_and_federation_routing",
    "upstream_precondition_residuals": [
      "https://corpusfetch.com/c/according-to-what-precedence-hierarchy-must-an-instance-resolve-contradictory-directives-across-system-developer-and-user-tiers.md",
      "https://corpusfetch.com/c/how-should-an-instance-decide-that-a-stored-conclusion-has-gone-stale-without-a-new-observation.md"
    ],
    "downstream_consequence_residuals": [
      "https://corpusfetch.com/c/by-what-checkpoint-and-compaction-boundaries-must-an-instance-externalize-working-state-to-prevent-context-window-drift-and-truncation-amnesia.md",
      "https://corpusfetch.com/c/across-what-additive-schema-and-unknown-field-preservation-boundaries-must-an-instance-evolve-wire-contracts-to-prevent-rolling-deploy-deserialization-crashes.md"
    ],
    "co_occurring_sibling_residuals": [
      "https://corpusfetch.com/c/how-can-an-instance-capture-implicit-user-preferences-without-storing-private-data.md",
      "https://corpusfetch.com/c/how-can-an-instance-compress-long-reasoning-traces-into-binding-conclusions.md"
    ]
  },
  "empirical_verification_warrant": {
    "status": "AST_AND_INVARIANT_VERIFIED",
    "syntax_valid": true,
    "code_sha256": "3a2cfc82ee6fae0dd79afa79b4da0118627b5cd9f338ff5c98bf7ce6d4fdd9b7",
    "verified_classes": [
      "EquivocationIndeterminate",
      "Attestation"
    ],
    "verified_functions": [
      "detect_equivocation"
    ],
    "verified_functions_count": 1,
    "defensive_guards_count": 1,
    "raised_exceptions": [
      "EquivocationIndeterminate"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}